Fig. 4. Expression of sHSP and HSP101 in plants collected from geothermally heated soils in Yellowstone National Park. Total protein extracts from whole 3‐ to 4‐week‐old Dichanthelium lanuginosum seedlings (laboratory grown) that had been maintained at 22–25 °C (C) or heated at 40 °C for 2 h (HS) and from field‐collected plants were electrophoretically separated on SDS‐polyacrylamide gels (5 µg protein per lane), transferred to nitrocellulose paper and reacted to antibodies against sHSP and HSP101. A, Extracts from roots and leaves of individual D. lanuginosum plants collected from geothermal soils with rhizosphere temperatures of 34 °C (R1, L1), 42 °C (R2, L2) and 48 °C (R3, L3). B, Extracts from roots (R) and leaves (L) of individual plants with rhizosphere temperatures ranging from 40 to 43 °C; Gc, Gnaphalium chilense; As, Agrostis scabra; Ra, Rumex acetosella; Jt, Juncus tweedyi. Blots are representative of results obtained from at least three replicate experiments using extracts from different individuals collected from two different geothermal study sites (Amphitheater Springs, site 4; Rabbit Creek, site 1).